A generic tank filler neck is known from the publication DE 20 2011 105 302 U1. This printed publication shows a filler neck, the filling line of which provides at the insertion end further away from the tank an annular volume lying radially on the outermost side of the filling line as a ventilation volume, in which gas through-flows, in the counter current to the simultaneously in-filled liquid, the tank filler neck in the direction of the insertion end. In this way, gas displaced by the in-filled liquid may escape through the filling line from the tank typically communicating with the tank filler neck.
During a filling process, the annular ventilation volume lying radially on the outermost side is typically limited radially outwards by the wall of the filling line and radially inwards by a wall of the breather pipe.
The generic solution mentioned above has a ventilation connection protruding laterally from the filling line, which in-feeds gas flowing in the direction of the insertion end only in the region of an outlet end of the breather pipe inserted in the insertion end of the filling line into the volume of the filling line to preferably prevent a collision of the fluids—displaced gas and in-fed liquid—flowing in opposite directions.
A further tank filler neck is known from the publication DE 10 2013 103 624 A1. Here also, a section at the insertion end of the filling line is used to provide the ventilation volume. Again, when the known tank filler neck carries out the filling according to specification, an annular gap between the radially inside situated breather pipe fed into the breather pipe and the radially outside lying wall of the filling line serves as a ventilation volume. In order to ensure a ventilation volume which is as uniform as possible in the circumferential direction around the breather pipe, ribs radially protrude from the inner side of the wall of the filling line serving as radial spacers between the breather pipe and the ventilation volume.
In these known tank filler necks it is disadvantageous that an operator using the tank filler neck according to specifications for filling a tank, who carries out the filling process or at least monitors the process near the tank filler neck, is inevitably bathed by the gas discharging from the insertion end of the filling line, which may at least result in an imposing odor. Depending on the composition of the gas discharging from the filling line, inhaling this gas may, in addition to the mere inconvenience, result also in a health hazard. Furthermore, in the case that the discharging gas is combustible, even an ignition or explosion hazard may result in the region of the insertion end.
A system made up of a tank filler neck, a tank and a ventilation line is known from the DE 10 2009 022 587 A1, in which the ventilation line ends at a distance from the filling line of the tank filler neck; however the solution known from this printed publication does not enable a ventilation of the filler neck itself but merely of the tank connected thereto.
Furthermore, known from the publication DE 10 2013 201 237 A1 is a ventilation valve enabling a ventilation of a fluid line; however, it does not have an insertion end for inserting a breather pipe. Rather, the ventilation valve only comprises a valve chamber having a float valve body movably provided therein and a ventilation opening which is, depending on the position of the float valve body, closed by the float valve body or released by it for through-flowing gas. Thus, the mentioned publication does not disclose a tank filler neck.